Hood Donald C, Anderson Susan, Rouleau Jacinthe, Wenick Adam S, Grover Larissa K, Behrens Myles M, Odel Jeffrey G, Lee Andrew G, Kardon Randy H
Department of Psychology, Columbia University, New York, New York 10027-7004, USA.
Ophthalmology. 2008 May;115(5):904-10. doi: 10.1016/j.ophtha.2007.06.001. Epub 2007 Sep 17.
To test a linear model relating the regional loss in retinal nerve fiber (RNFL) thickness to the corresponding regional loss in sensitivity with data from patients with previous anterior ischemic optic neuropathy (AION).
Case-control study.
Twenty-four individuals with AION and 20 with normal vision were tested. The time since the AION attack ranged from 5.2 months to more than 20.3 years (median, 2.95 years).
Eyes were tested with standard automated perimetry (SAP) and with optical coherence tomography (OCT), both RNFL thickness scans. The average RNFL thickness of the inferior and superior disc sectors was plotted against the average total deviations (linear units) of the corresponding superior and inferior arcuate field regions, and a linear model was fitted. According to the model, the RNFL thickness R=s(o)T+b, (1), where T is the relative SAP sensitivity loss (on a linear scale; e.g., for -3 dB, T = 0.5), s(o) is the RNFL thickness attributable to axons in the healthy or normal state (T = 1.0), and b is the residual RNFL measured when all sensitivity and axons are lost.
Optical coherence tomography RNFL thickness and SAP sensitivity.
The data from the AION patients resembled the data from glaucoma patients previously tested and were described by the linear model. For patients with SAP losses of more than -10 dB in the arcuate region, the RNFL thickness provided an estimate of residual RNFL thickness, b. The median value of b (45.5 microm) was similar to the value for patients with glaucoma. It varied among individuals (range, 30.4-63.3 microm), showing a very weak correlation with patient's age (r = 0.30) and the time since the AION episode (r = 0.26), but an excellent correlation (r(2) = 0.94; P<0.01) with the value of s(o), estimated from the unaffected eyes.
The relationship between a structure (OCT RNFL thickness) and function (SAP sensitivity loss) is the same for patients with AION and glaucoma and can be approximated by a simple linear model. The model may provide a framework for identifying those patients with ganglion cell axons that are malfunctioning but are alive.
利用既往有前部缺血性视神经病变（AION）患者的数据，测试一个将视网膜神经纤维层（RNFL）厚度的区域损失与相应区域的敏感度损失相关联的线性模型。
病例对照研究。
对24例AION患者和20例视力正常者进行了测试。AION发作后的时间范围为5.2个月至20.3年以上（中位数为2.95年）。
使用标准自动视野计（SAP）和光学相干断层扫描（OCT）对眼睛进行测试，二者均为RNFL厚度扫描。将视盘上下扇形区域的平均RNFL厚度与相应的上下弓形视野区域的平均总偏差（线性单位）进行绘图，并拟合一个线性模型。根据该模型，RNFL厚度R = s(o)T + b，（1）式中，T为相对SAP敏感度损失（线性尺度；例如，对于-3 dB，T = 0.5），s(o)为健康或正常状态下轴突所致的RNFL厚度（T = 1.0），b为所有敏感度和轴突丧失时测量的残余RNFL。
光学相干断层扫描RNFL厚度和SAP敏感度。
AION患者的数据与先前测试的青光眼患者的数据相似，并可用线性模型描述。对于弓形区域SAP损失超过-10 dB的患者，RNFL厚度可提供残余RNFL厚度b的估计值。b的中位数（45.5微米）与青光眼患者的值相似。其在个体间有所不同（范围为30.4 - 63.3微米），与患者年龄（r = 0.30）和AION发作后的时间（r = 0.26）的相关性较弱，但与从未受影响眼睛估计的s(o)值具有极好的相关性（r² = 0.94；P<0.01）。
AION患者和青光眼患者的结构（光学相干断层扫描RNFL厚度）与功能（SAP敏感度损失）之间的关系相同，并且可以用一个简单的线性模型来近似。该模型可为识别那些神经节细胞轴突功能异常但仍存活的患者提供一个框架。
